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 "the path of least resistance is through a vacuum"

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SP12-SE preamp for Dave P.



front view (extra thick 4mm panel)



rear view (also note "thumbnut" on phono ground)   (extra thick 3mm panel)



left above - extra power supply filtering for phono             right above - isolation mounts on phono PCB



inside view - "iso-damp" material under both PCBs, large toroid power, large Mundorf silver/oil capacitors



inside rear panel detail- IEC AC filter, power supply choke, "custom-built" label,
also note rear panel is on a "frame" support same as front panel



inside rear panel detail - input/output ground buss



inside front panel - TKD volume, Goldpoint selector switch, dual mono gain/balance attenuators



inside front panel detail



here's a followup note that Dave sent about his preamp after using it for a few months . . . . .

After owning and listening to the preamp you built me for several months now, I thought Id write my thoughts and experiences. 
Iíll begin by saying I looked long and hard at many other makers of tube preamps. The obvious bigger names should come come to mind. 
While many of these makers have fine products. Most had build techniques I prefer not to see. Things like RCA jacks on PCBs, large numbers of OPAMPs in the design, 
excessive tube counts, features I donít want or need and overall bloat in the build. Im sure many of these preamps are fine units but they simply didnít do it for me. 
So now after living with my pick and using it for months, Im confident I made the right decision. So confident if I could do it all over again, I wouldnít change a thing. 
After using  this pre with many different sources and amps, the one feature of the pre that I thought I didnít need, wound up being one I could not not be without now. 
The left and right gain adjustment. When  I tried a few different amps with this pre I discovered tuning the gain to an optimal level for best performance was a must.  
This became so apparent it made me wonder why so few major makers donít have these adjustments in their units. Probably not needed if you stick with one brand but clearly needed for my needs. 
Obviously price was a major decider for me also. And I must say, at the roughly $1500 I spent on this pre, there wasnít much like it to compare with. 
Clearly there are used models out there from some of the bigger names. But again, there were certain build aspects as those described above that I wanted to avoid. 
And none of what I could find in the sub $2000 used market had this. There are other small outfits like tubes4hifi that make preamps in this range. Some with large followings too. 
However I could not find one that had the same level of build quality and looks that matched that of this preamp. 
And factoring in Royís willingness to make a few design / part changes to my liking, it was a no brainer. 
Lastly, after letting the pre burn in for weeks, I finally decided to try the pre with the used RCA cleartop 12AU7s I bought with it. Wow, yes it likes tube rolling. 
Really made the pre come alive in other ways than I had heard before with the stock JJ tubes. The mid range got better. Bass seemed to get a little deeper. 
And the highs seemed to tame themselves a bit. Not that the pre was ever edgy to my ears. So in closing. Im a happy owner of preamp I feel is not easily matched at its price point. 
Im happy with my purchase and donít have any buyers remorse months after its purchase and use. And when one adds Royís support, the value really becomes un-matched. 
His quick response to email questions and concerns. And in my case, fast turn around time after I mistakenly sent in the unit for an un-needed repair, thanks Roy. 
It has really become apparent I made the right choice for my money. This is one happy owner.
Thanks
Dave

send us email at: info@tubes4hifi.com


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 tubes 4 hifi
 "the path of least resistance is through a vacuum"